I was looking at my swash driver arms on my low fbl head and I noticed that they are not horizontal when the swash is at 0 pitch. I was trying to figure out if there was a reason, and the only thing I could come up with was that possibly because the arms are sort of too long when used on the low fbl head, and maybe they were trying to bring the the swash followers more level.

So what I was thinking is why couldn't I just cut 5mm or so off the main shaft, re drill the hole (providing I can, I have the hollow main shaft which I think is hardened), and lower the head another 5mm to get the swash driver arm to sit level at 0 pitch. Right now they sit level at max pitch (12 degrees). There would still be plenty of room for the swash to move, I checked that. And I realize it would be difficult to get the hole drilled in the perfect spot, but I think I have the right equipment and know how to do it.

So I was curious if other people's swash driver arms sit like that, or if it is just mine. I tried google images for low fbl head protos's but there was like nothing. Here's what mine looks like at -12, 0, and +12.

They are just swash drivers, not mixing arms as in a flybar head. They don't have to be parallel at midstick for any reason at all. In a flybar head they would have linkages attached and therefore need to be parallel at midstick for proper geometry. Leave well enogh alone LOL! and I sure as hell would not lower the main shaft any more that is for sure! Both the protos low fbl head and mini protos low fbl head are like this as is the rjx 450 fbl head and many others. Again they are just swash drivers and nothing more.

Well I did fly today, but here in ND the weather has been making it difficult. Today was the first nice day in a while where nice means not really windy, not snowing, and temp above 25. So I get bored on all the other days...

Your swash is riding too low. At -12 if you give cyclic input it will bind on the frame. Lengthen the servo to swash links. My servo to swash is 31mm and swash to grips 28mm (inside length). 12degrees collective and 12 cyclic with no binding at all at step L of beastx menu.